Hex wrenches, also known as Allen keys, are the tools you use to screw and unscrew fasteners that have a hexagonal recess (as opposed to a Phillips or flathead recess). Hex screws are commonly used on ...

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Screws may be commonplace, but that doesn't mean they're simple. A screw is any shaft with a corkscrew groove carved around its surface and, regardless of their design, screws are usually used to ...